Method of forming thermoplastic fasteners



March 3, 1942. MARINSKY 2,274,722

METHOD OF FORMING THERMOPLASTIC FASTENERS Original Filed March 6, 193? INVENTOR 0a wm Mew/many ATTOR EY v Patented Mar. 1?, 1942 UNITED STATES PATENT IOFFICE METHOD OF FORMING THERMOPLASTIC FASTENERS Davis Marinsky, Bronx, N. Y., assignolg'by mesne assignments, of one-half to said Davis Marinsky, and one-half to Louis H. Morin, Bronx,

Original application March 6, 1937, Serial- No. 129,316. Divided and this application August 10, 1938, Serial No. 224,008

2 Claims.

This invention relates to separable fasteners employinglinked stringers adapted to be coupled and uncoupled by a slider movable longitudinally of the links of said stringer in coupling and unof to contact the respective links to aid in securing or cementing the links to the stringers, especially when subjecting the stringer tapes to a saturating solution in the form of a solvent, suchfor example as acetone which, by capillary attraction, extends to the inner surfaces of the 'links where they contact the tapes to form a cementing area between the links and tape. This structure and method is in accordance with the teachings in my companion application Serial No. 129,321, filed March 6, 1937. If desired, slight pressure may be applied to the links-in the cementing operation'as well as the application of .heat suflicient only to aid in setting or hardening ance with the method more fully hereinafter described and claimed.

The invention is fully disclosed in the following specification, of which the accompanying drawing forms a part, in which the several parts of my invention are designated by suitable reference characters in each of the views, and in which:

Fig.1 is a plan view of a fastener made according to my invention, with part of the construction broken awaysv Fig. 2 is a detail view' of one end of a fastener stringer diagrammatically illustrating the method of stacking orbunching links thereon.

Fig. 3 is an enlarged detail edge view of one stringer, diagrammatically showing the method of securing the bunched or-stacked links together,

said figure being a view substantially looking in the direction of the'arrows 3-4 of Fig. 1.

Fig. 4 is a partial section on the line 4-4 of Fig. '1, showing the other end stop which I employ; and i Fig. 5 is a view similar toFig. 4 showing a modified form of construction.

In Fig. 1 of the drawing. I have shown at It" and H the stringers of a separable fastener having attached to the beaded edges l2 and Hi thereof a plurality of longitudinally spaced coupling links l4 and I5. At. It, I have shown a slider movable longitudinally of the links to couple and uncouple the same, said slider having a finger piece or pull I! to facilitate the operation thereof. i

. The links M and IS in the'construction shown are preferably made from a plastic or-thermoplastic material, such for example as cellulose acetate. These links may be clamped upon the stringer tapes In, H, or the beaded edges [2, l3 thereof or directly die cast thereon. It is preferred that the beaded edges have rayon or other the cement, all as taught in a companion application filed March 6, 1937, Ser. No. 129,321.

In the operation of forming my improved stringers orthe end stopsat the ends of said stringers, each stringer tape is formed in the conventional manner with all of the links l4l5 applied thereto in an equally spaced manner.

The first'step in forming end stops III at one end of the stringer is as follows. Four of the end links are forced longitudinally of the stringer tape bya suitable fork-shaped tool I! as indicated in Fig. 2 of the drawing in which the links H are shown on the tape to. This operation is performed after acetone or slight heat has been applied to said four links to soften the same sufllciently to provide free action or sliding movement longitudinally of the beaded edge l2 of the tape, and especially in the case of die cast links which are applied to said tapes. When these links are brought into the stacked orpiled relationship with the projecting beads I811 of the links extending into recesses on the opposed surface of adjacent links, said links are then secured together by applying a suitable cement or solvent thereto, for example, by spraying a cement or solvent such as acetone in the manner indicated at 2|! in Fig. 3 of the drawing to one orboth side surfaces of the links, and then allowing the solvent or cement to dry. If desired, slight pressure may'be applied to the links in this operation.

However, if allof the links areto be cemented to the tapes H! as abovestated, the pressing operation may be performed in the aforesaid cementing operation. All of the stacked or grouped links forming the end stops IS, in addition to being cemented together on adjacent abutting surf faces, will also be cemented to the tape lIl-orthe headed edge thereof.

In the accompanying drawing, the and stop l8 on the stringer l0 consists of five links wherestrands Ila, 13a extending longitudinally thereat as the stop It on the stringer ll consists of four finished end to the complete stringer. But, if

desired, any number of the links may be provided, it being understood that two links joined on each stringer will block or stop further progress of the slider along the stringers. With the present construction, the slider I6 is capable of extending the full length of the stringers or to a point in alinement with the outer link of each stop It, or substantially so.

End stops such as l8 will provide a neat and I finished appearance to one end of the stringers,

and a uniform construction will be provided throughout the entire stringer in so far as the 'link and end stop I8 is concerned. The same result or substantially the same result can also be accomplished at the other end of the stringers by simply providing a stop plate or sheet 2| of cellulose acetate or similar material, preferably of a color consistent'with that of the color employed in the links H and I5. I I

This plate 2| is arranged upon a number of the interlocked end links 22 of the stringers l and l I and is secured thereto by a cement or adhesive 23 such for example as acetone which may first be spread onto the coupled links 22 and onto one surface of the plate 2|, and then said plate attached or mounted in position in the manner shown in Fig. 1 of the drawing and slight pressure may be applied to secure and retain the plate 2| in position, and this may be done in the presence of heat if desired.

In Fig. 5 of the drawing, I have shown a modification which consists simply in including a simplemental stop plate 2la at the lower surface of the stringers to provide a double stop. The

plate 2la is secured in position at the same time that the plate 2| is secured or directly thereafter as may be desired. By using acetone or cellulose acetate fasteners a substantial weld is provided between the parts secured together which provides a strong and durable construction. Thus, it will be seen that a very simple and economical form of end stop is provided for both ends of the stringers whileat the same time eliminating the use of metallic parts or parts of complicated construction, thus materially reducing the 'cost of manufacture of the complete device.

The slider It as well as the pull l'l may also be composed of plastic material of the type and links, but this is simply to provide a balanced kind under consideration, but these members form no specific part of the present invention.

This invention constitutes a division of my prior application Serial No. 129,316, filed March 6, 1937.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. The herein described meth of forming end stops on the stringers of se arable fasteners, said stringers having cellulose acetate links including coupling portions arranged longitudinally thereof normally in equally spaced relationship to each other, moving predetermined end links at one end of each stringer longitudinally of the stringer in the direction of the other links thereon to stack and nest a predetermined number of said links including the coupling portions thereof, then securing said stacked and nested links together with a suitable cement to form a blocking end stop at said end of 'each'stringer, coupling predetermined links at the other ends of the stringers together, and then applying a suitable cement to said coupled links to secure said links against separation and applying a stop plate to the secured links in the operation of cementing said links together to form an end stop at said last named end of both stringers.

2. The herein described method of forming the stringers of separable fasteners, which consists in providing fabric stringer tapes, attaching thermoplastic links having coupling portions to one edge portion of each tape at longitudinally spaced intervals, including the coupling rortion of the end links of opposed stringers at one end thereof, applying a solvent cement to the coupled links at said end of the stringers to unite said coupled links, cementing a stop plate to said coupled links in the operation of cementing said links together in forming an end stop at said coupled end of the stringers, moving predetermined links at the other end of each stringer longitudinally of the stringer in the direction of the other links thereon to stack and nest a predetermined number of said links, securing the stacked and nested links together with a suitable cement to form an end stop at the last named end of the stringers, and treating the stringer tapes with a link solvent to cement all of the links to said tapes.

DAVIS MARINSKY. 

